libxtables: linked-list name<->id map

This consolidates the maps from libxt_devgroup and libxt_realm.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

diff --git a/include/xtables.h.in b/include/xtables.h.in
index c361bdbdc57c30ca0a34e19fbcb87f4564dd7729..30d9e73b10f613d7839cbc4644b3b167ee25d0d4 100644 (file)
--- a/include/xtables.h.in
+++ b/include/xtables.h.in
@@ -134,6 +134,16 @@ struct xt_fcheck_call {
        unsigned int xflags;
 };
 
+/**
+ * A "linear"/linked-list based name<->id map, for files similar to
+ * /etc/iproute2/.
+ */
+struct xtables_lmap {
+       char *name;
+       int id;
+       struct xtables_lmap *next;
+};
+
 /* Include file for additions: new matches and targets. */
 struct xtables_match
 {
@@ -418,6 +428,11 @@ extern void xtables_option_mfcall(struct xtables_match *);
 extern void xtables_options_fcheck(const char *, unsigned int,
                                   const struct xt_option_entry *);
 
+extern struct xtables_lmap *xtables_lmap_init(const char *);
+extern void xtables_lmap_free(struct xtables_lmap *);
+extern int xtables_lmap_name2id(const struct xtables_lmap *, const char *);
+extern const char *xtables_lmap_id2name(const struct xtables_lmap *, int);
+
 #ifdef XTABLES_INTERNAL
 
 /* Shipped modules rely on this... */

diff --git a/xtoptions.c b/xtoptions.c
index 42063144d49bdf1854739af7722691c1a7536a3f..f48c011c86b4120f1a22859d74e423ab1324444d 100644 (file)
--- a/xtoptions.c
+++ b/xtoptions.c
@@ -7,6 +7,7 @@
  *     published by the Free Software Foundation; either version 2 of
  *     the License, or (at your option) any later version.
  */
+#include <ctype.h>
 #include <errno.h>
 #include <getopt.h>
 #include <limits.h>
@@ -487,3 +488,101 @@ void xtables_option_mfcall(struct xtables_match *m)
        if (m->x6_options != NULL)
                xtables_options_fcheck(m->name, m->mflags, m->x6_options);
 }
+
+struct xtables_lmap *xtables_lmap_init(const char *file)
+{
+       struct xtables_lmap *lmap_head = NULL, *lmap_prev = NULL, *lmap_this;
+       char buf[512];
+       FILE *fp;
+       char *cur, *nxt;
+       int id;
+
+       fp = fopen(file, "re");
+       if (fp == NULL)
+               return NULL;
+
+       while (fgets(buf, sizeof(buf), fp) != NULL) {
+               cur = buf;
+               while (isspace(*cur))
+                       ++cur;
+               if (*cur == '#' || *cur == '\n' || *cur == '\0')
+                       continue;
+
+               /* iproute2 allows hex and dec format */
+               errno = 0;
+               id = strtoul(cur, &nxt, strncmp(cur, "0x", 2) == 0 ? 16 : 10);
+               if (nxt == cur || errno != 0)
+                       continue;
+
+               /* same boundaries as in iproute2 */
+               if (id < 0 || id > 255)
+                       continue;
+               cur = nxt;
+
+               if (!isspace(*cur))
+                       continue;
+               while (isspace(*cur))
+                       ++cur;
+               if (*cur == '#' || *cur == '\n' || *cur == '\0')
+                       continue;
+               nxt = cur;
+               while (*nxt != '\0' && !isspace(*nxt))
+                       ++nxt;
+               if (nxt == cur)
+                       continue;
+               *nxt = '\0';
+
+               /* found valid data */
+               lmap_this = malloc(sizeof(*lmap_this));
+               if (lmap_this == NULL) {
+                       perror("malloc");
+                       goto out;
+               }
+               lmap_this->id   = id;
+               lmap_this->name = strdup(cur);
+               if (lmap_this->name == NULL) {
+                       free(lmap_this);
+                       goto out;
+               }
+               lmap_this->next = NULL;
+
+               if (lmap_prev != NULL)
+                       lmap_prev->next = lmap_this;
+               else
+                       lmap_head = lmap_this;
+               lmap_prev = lmap_this;
+       }
+
+       fclose(fp);
+       return lmap_head;
+ out:
+       xtables_lmap_free(lmap_head);
+       return NULL;
+}
+
+void xtables_lmap_free(struct xtables_lmap *head)
+{
+       struct xtables_lmap *next;
+
+       for (; head != NULL; head = next) {
+               next = head->next;
+               free(head->name);
+               free(head);
+       }
+}
+
+int xtables_lmap_name2id(const struct xtables_lmap *head, const char *name)
+{
+       for (; head != NULL; head = head->next)
+               if (strcmp(head->name, name) == 0)
+                       return head->id;
+       return -1;
+}
+
+const char *xtables_lmap_id2name(const struct xtables_lmap *head, int id)
+{
+       for (; head != NULL; head = head->next)
+               if (head->id == id)
+                       return head->name;
+       return NULL;
+}